Re: hard shiny plastic kitchen handles
The acetone in the nail polish remover has etched the surface of the plastic. This is something you have to be very careful of when using acetone based products on plastics. Acetone products melt plastic, that's all there is to it, and it should be used sparingly and with extreme caution.
Can you return the shine? Maybe, as long as the etch isn't too deep. It is doubtful that you'll ever return them to their original shine, but the lacquer suggestion might help some.
In the future, when you need to remove paint from a surface, start with paint thinner, as it is much more gentle and plastic friendly. If paint thinner doesn't work, then you can graduate to either brake fluid (yes, the stuff used in your car brake system, purchased from an auto parts store ), or lacquer thinner.
Of these three products, the brake fluid will be the most gentle, with paint thinner coming in a close second. Lacquer thinner isn't particularly caustic, but it can deform some plastics and synthetics, so test it first and use it cautiously.
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